3 research outputs found
Mechanocatalytic Depolymerization of Dry (Ligno)cellulose As an Entry Process for High-Yield Production of Furfurals
Driven by mechanical forces, the
acid-catalyzed depolymerization of solid biomass completely overcomes
the problems posed by the recalcitrance of lignocellulose. The solid-state
reaction leads to water-soluble oligosaccharides, which display higher
reactivity than cellulose and hemicellulose. Here, we show that water-soluble
oligosaccharides are useful feedstock for the high-yield production
of 5-hydroxymethylfurfural (HMF) and furfural in biphasic reactors.
This is because they readily undergo hydrolysis upon microwave heating,
selectively forming monosaccharides as intermediates in the aqueous
phase. Short reaction times are possible with the use of microwave
heating and limit the extent of degradation reactions. This work provides
an ionic-liquid-free approach to process lignocellulosic substrates
into HMF and furfural with high yields. In fact, starting this novel
approach with α-cellulose, yields of HMF of 79% and furfural
of 80% at 443 K for 9 min were obtained. The processing of real lignocellulose
(e.g., beechwood and sugar cane bagasse) also achieved high yields
of HMF and furfural. Thereby, the current results indicate that the
process limitation lies no longer in the recalcitrance of lignocellulose,
but in the extraction of highly reactive HMF and furfural from the
aqueous phase in the biphasic reactor